Many computing applications require access to a data source having relatively stable information, i.e., information that changes infrequently. Applications using reference information include dictionaries, reference databases, map display programs, engineering drawing display programs, among others. Oftentimes, reference information is published on read-only memory devices, such as a compact disk read-only memory (CD-ROM) device, or other write-protected media, and distributed for use in such computing applications. Occasionally, such reference information must be replaced or otherwise updated to ensure that current information is being used in the respective applications. A typical solution is the replacement of the reference material media with new media containing updated information. Depending on the frequency of such updates, this update process can involve significant expense. Moreover, there may be a critical need to provide updates to certain applications in an expedient manner for immediate use by the application.
Consider an application in which field workers must have ready access to the most current information in order to provide customer service. These field workers may use portable computing devices, such as laptop computers, in order to provide on-site service. Most of the information required to satisfy the particular application may be relatively static, and thus may be suitable for distribution on read-only media, such as a CD-ROM device. However, relatively minor periodic updates may be needed to keep the reference information current. A practical method for providing the necessary updates in a time and cost efficient manner is useful for such applications.
It is desirable to have a system in which read-only data provides a primary source of information, yet which provides for the update of such information in an expedient and cost effective manner.